Endoscopic vitrectomy improves outcomes of Seoul-type keratoprosthesis exchange in rabbit model.

PURPOSE To investigate the efficacy of an endoscopic vitrectomy in Seoul-type keratoprosthesis (S-Kpro) exchange procedures. METHODS Nine S-Kpro-implanted rabbit eyes were enrolled in the S-Kpro exchange. Six eyes underwent an antecedent vitrectomy by an endoscopic system and then the S-Kpro exchange (endoscopy group). In the other three eyes, previously placed S-Kpros were removed, and a conventional vitrectomy was performed using the Eckardt keratoprosthesis, followed by an implantation of new S-Kpros (Eckardt group). All eyes were evaluated with slit lamp biomicroscopy and ultrasonography weekly to evaluate the time up to the development of the total retinal detachment (RD). RESULTS Vitreous traction membranes were found around the prolene haptics of the fixation sites in all the S-Kpro implanted rabbits; they were excised precisely through an endoscopic view in the endoscopy group. The mean survival time up to the RD development was 9.75 +/- 4.70 weeks in the endoscopy group. In contrast, total retinal detachment or dialysis over 180 degrees developed during surgery in all three eyes in the Eckardt group. CONCLUSIONS Antecedent endoscopic vitrectomy was safe and effective for the S-Kpro exchange in a rabbit model by removing the vitreous traction near the haptics before the exchange procedures.